In addition to the main story, "Future Past," and the additional stories, "The Future of Hyuga" and "New Enemies," "The Labyrinth of Yomi" features a never-before-told story that reveals the past and ultimate destinies of Kaguya and her friends.
It also features multiple endings, based on the player's actions. You must face a malicious enemy at the end of the dungeon, and the "true ending" reveals the fates of the three sisters.